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BENZODIAZEPINE EQUIVALENCE TABLE
(Benzodiazepine Equivalency Table)

Revised April 2007

This Benzodiazepine Equivalence Table is based on the extensive research and clinical experience of Professor C Heather Ashton, DM, FRCP, Emeritus Professor of Clinical Psychopharmacology at the University of Newcastle upon Tyne, England. Sources: NRHA Drug Newsletter, April 1985 and Benzodiazepines: How they Work & How to Withdraw (The Ashton Manual), 2002. The approximate equivalent doses to 10mg diazepam (Valium) are given.

For a discussion of half-lives and equivalencies see also the Benzo FAQ document.

Benzodiazepines1
Half-life (hrs)2
[active metabolite]
Approximately Equivalent
Oral dosages (mg)3
Market Aim4
Alprazolam
(Xanax, Xanor, Tafil)
6-12
0.5
a
Bromazepam
(Lexotan, Lexomil)
10-20
5-6
a
Chlordiazepoxide
(Librium)
5-30 [36-200]
25
a
Clobazam
(Frisium)5
12-60
20
a,e
Clonazepam
(Klonopin, Rivotril)5
18-50
0.5
a,e
Clorazepate
(Tranxene)
[36-200]
15
a
Diazepam
(Valium)
20-100 [36-200]
10
a
Estazolam
(ProSom, Nuctalon)
10-24
1-2
h
Flunitrazepam
(Rohypnol)
18-26 [36-200]
1
h
Flurazepam
(Dalmane)
[40-250]
15-30
h
Halazepam
(Paxipam)
[30-100]
20
a
Ketazolam
(Anxon)
30-100 [36-200]
15-30
a
Loprazolam
(Dormonoct)
6-12
1-2
h
Lorazepam
(Ativan, Temesta, Tavor)
10-20
1
a
Lormetazepam
(Noctamid)
10-12
1-2
h
Medazepam
(Nobrium)
36-200
10
a
Nitrazepam
(Mogadon)
15-38
10
h
Nordazepam
(Nordaz, Calmday)
36-200
10
a
Oxazepam
(Serax, Serenid,
Serepax, Seresta)
4-15
20
a
Prazepam
(Centrax, Lysanxia)
[36-200]
10-20
a
Quazepam (Doral)
25-100
20
h
Temazepam
(Restoril, Normison,
Euhypnos)
8-22
20
h
Triazolam
(Halcion)
2
0.5
h
Non-benzodiazepines
with similar effects 1, 6
 
 
 
Zaleplon
(Sonata)
2
20
h
Zolpidem
(Ambien, Stilnoct, Stilnox)
2
20
h
Zopiclone
(Zimovane, Imovane)
5-6
15
h
Eszopiclone
(Lunesta)
6
(9 in elderly)
3
h

  1. All these drugs are recommended for short-term use only (2-4 weeks maximum). See 1988 Guidelines.

  2. Half-life: time taken for blood concentration to fall to half its peak value after a single dose. Half-life of active metabolite shown in square brackets. This time may vary considerably between individuals.

  3. These equivalents do not agree with those used by some authors. They are firmly based on clinical experience during switch-over to diazepam at start of withdrawal programs but may vary between individuals.

  4. Market Aim: Although all benzodiazepines have similar actions, they are usually marketed as anxiolytics (a), hypnotics (h) or anticonvulsants (e).

  5. In the UK clobazam (Frisium) and clonazepam (Rivotril) are licensed for use as anti-epileptics only.

  6. These drugs are chemically different from benzodiazepines but have the same effects on the body and act by the same mechanisms.

The Ashton Manual · Professor Ashton's Main Page


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